Using a Dremel to Drill Through Glass

I'm trying to drill a hole in a 1/4 in. piece of glass with my Dremel tool. I have a diamond tipped bit with a rounded end. The Dremel is a single speed Multi-pro 30,000 rpm. It just seems to be taking a really long time to get through it. How long should it take?

The instructions that came with the bit indicated that I should go slow and moisten frequently which I am doing. My concern is that perhaps I have the wrong Dremel model? Any suggestions from the experts would be greatly appreciated.

I tried to drill holes in the bottom of mason jars to make bird feeders with my dremmel and a diamond bit and it took forever. I switched to a regular drill and a glass bit and worked in no time. A spray bottle with water in it sprayed on the glass made it even faster.

Be sure to put blue or masking tape on the jar where you want to drill. That prevents the drill from chattering across the glass when you start the drilling. The tape also keeps little glass shards from shooting out as you drill. Be sure to also do it over a table so tiny pieces of glass don't get onto the floor and gets stepped on. It took awhile to drill the hole, but it worked.